irqchip/gic-v3-its: Don't WARN on LPI free allocation failure

free_lpi_range() cannot give LPIs back to the allocator without
allocating a struct lpi_range to describe the freed range, so it
returns -ENOMEM (its only failure mode) when that allocation fails,
and its_lpi_free() turns this into a WARN_ON().

syzbot triggers the WARN_ON() by injecting a slab allocation failure
on device teardown, which with panic_on_warn becomes a panic:

  WARNING: drivers/irqchip/irq-gic-v3-its.c:2251 at its_msi_teardown+0x3a4/0x424
   its_msi_teardown+0x3a4/0x424
   msi_remove_device_irq_domain+0x16c/0x27c
   msi_device_data_release+0x38/0x9c

The failure is transient and the consequence benign: the freed range
is simply never returned to the allocator. This does not warrant a
WARN_ON() backtrace, so log a rate-limited error instead.

Fixes: 880cb3cddd16 ("irqchip/gic-v3-its: Refactor LPI allocator")
Reported-by: syzbot+229d761b8a110e6de517@syzkaller.appspotmail.com
Signed-off-by: Karl Mehltretter <kmehltretter@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Assisted-by: Claude:claude-fable-5
Link: https://patch.msgid.link/20260811095532.48454-1-kmehltretter@gmail.com
Closes: https://syzkaller.appspot.com/bug?extid=229d761b8a110e6de517

0 files changed, 0 insertions, 0 deletions